In my patent application Ser. No. 10/337,531, filed Jan. 7, 2003 and entitled “Piezoelectric Transducer with Gas Matrix”, I disclose a novel transducer which comprises a plurality of piezoelectric cylinders. The axial length and composition of the piezoelectric cylinders determine the frequency of the transducers when excited. The axial ends of the piezoelectric cylinders are aligned with the faces. The piezoelectric cylinders are separated from each other in a manner to substantially reduce or substantially eliminate crosstalk. The piezoelectric cylinders or fibers may be separated from each other by a space that is empty or a space that is partially empty of matrix material resulting in a gap between the cylinders and the material so that the cylinders and material are substantially entirely unconnected. The piezoelectric cylinders are separated from each other by a distance that is preferably less than the acoustic wavelength at the frequency of the piezoelectric cylinders (rods) or fibers in the space between the cylinders. Electrodes are provided at the faces of the transducer for simultaneously exciting the piezoelectric cylinders.
The piezoelectric cylinders may have one or more of the following cross sections: circular, rectangular, hexagonal, or any other polygon, with a width preferably less than one wavelength of the frequency in the piezoelectric material. The matrix material may comprise a solidified foam, fiber batting, or honeycomb, for example, which material is not electrically conductive. The gap in the space between the piezoelectric cylinders may be filled with a gas at atmospheric pressure, gas below atmospheric pressure, or a vacuum.
It is an object, according to the present invention, to provide a novel method for the manufacture of gas matrix piezoelectric transducers and actuators.